On Wed, Jun 16, 2021 at 06:30:43PM -0700, Andrew Morton wrote: > On Wed, 16 Jun 2021 00:54:15 -0400 Johannes Weiner <hannes@xxxxxxxxxxx> wrote: > > On Wed, Jun 16, 2021 at 11:20:08AM +1000, Dave Chinner wrote: > > > On Tue, Jun 15, 2021 at 02:50:09PM -0400, Johannes Weiner wrote: > > > > On Tue, Jun 15, 2021 at 04:26:40PM +1000, Dave Chinner wrote: > > > > > On Mon, Jun 14, 2021 at 05:19:04PM -0400, Johannes Weiner wrote: > > > > > > @@ -1123,6 +1125,9 @@ static int __remove_mapping(struct address_space *mapping, struct page *page, > > > > > > shadow = workingset_eviction(page, target_memcg); > > > > > > __delete_from_page_cache(page, shadow); > > > > > > xa_unlock_irq(&mapping->i_pages); > > > > > > + if (mapping_shrinkable(mapping)) > > > > > > + inode_add_lru(mapping->host); > > > > > > + spin_unlock(&mapping->host->i_lock); > > > > > > > > > > > > > > > > No. Inode locks have absolutely no place serialising core vmscan > > > > > algorithms. > > > > > > > > What if, and hear me out on this one, core vmscan algorithms change > > > > the state of the inode? > > > > > > Then the core vmscan algorithm has a layering violation. > > > > You're just playing a word game here. > > Don't think so. David is quite correct in saying that vmscan shouldn't > mess with inode state unless it's via address_space_operations? It seemed to me the complaint was more about vmscan propagating this state into the inode in general - effecting fs inode acquisitions and LRU manipulations from the page reclaim callstack - regardless of whether they are open-coded or indirect through API functions? Since I mentioned better encapsulation but received no response...
